Paint and pigment



Patented Apr.8,19.24.

FRANK E. sacmmm, or rear HENRY, new YORK.

PAINT AND PIGMENT.

No Drawing. Application filed April 2,

To all whom it may concern:

Be it known that I, FRANK E. BACHMAN, residing at Port Henry,'Essex County, New York, have invented a new and useful Im- 6 provement in Paints and Pigments, of which the following is a full, clear, and exact description.

My invention relates to paints and especially those paints and pigments which 1 are composed to a greater or less extent of hydrated titanic oxide, and more especially to hydrated titanic oxide, known as modified meta titanic acid, described in my pending applicatiops for patents, Serial No. 285 87 3,

s filed March 28,1919 and'Serial No. 4531355,

filed March 18, 1921.

The objects of my invention comprise paints composed of modified meta titanic acid, which are improved in certain particulars, as for instance, their resistance to wear and their drying and hardening qualities. It has not been disclosed heretofore that meta titanic acid or modified meta titanic acid could be used for paint manufacture.

I have found'that both of them, but. more especially modified meta titanic acid freed from such impurities as sulphuric anhydrides and chlorine, have, when manufactured into paints, greater hiding and cov- 0 ering power than has the titanic oxide heretofore commercially producible. The use of titanic oxide as a pigment has been long known both in chemical and mechanical combinations with other substances, such as roasted 'ilmenite, red mud andsludge from bauxite ores, titanium carbide, and as pure v titanic oxide uncombined with other substances.

The'manufacture of titanic oxide for pigment is always carried out-by bringing 1t Jinto acid solution'with hydrochloric or sul phuric acid, together .with such soluble impurities as iron, which the rawmaterial may contain, and separating the titaniumfrom the solution as an amorphous hydrated titanic oxide. When .this oxide is separated from hydrochloric acid solution, it always carries with it chlorine, which is supposed to be present as a titanium hydrochlo ride. Whenseparated from sulphuricv acid solutions, it contains" sulphuric acid, supposed to be combined to. form basic titamc The basic titanic sulphate pres "sulphate. I

out varies in' uantity from 9% to 31%. The

precipitates a 0 contain iron, varying -with 1921. serial No. 458,020.

the amount of iron present in the solution, I

gether with the combined water by heating to temperatures sufficiently high to decompose the sulphates or chlorides present. When the hydrates are heated, they give ofl theircombined water at temperatures under 900 F., but are not entirely freed from S0 and chlorine, even after heating to 1500 F. At 1100 F., basic titanic sulphate begins to give oil S0 and at the same temperature, titanic oxide begins to change from a so amorphous powder to one containing hard gritty particles which greatly reduce its value as a pigment. If the heating is carried to the temperature necessary to render it relatively free from S0,, it becomes so hard and gritty as to be of little value as a pigment. Owing to the greater cost and difficulties 1n manufacture, hydrochloric acid solutions are not available for commercial manufacture of titanic oxide or modified metatitanic acid pigments. If titanic oxide or modified metatitanic acidwhich contains appreciable amounts of S0,, that is, amounts in excess of .35%'are manufactured into paints, the acid reacts to cause the paint produced t9 rapidly deteriorate by changing to a yellowish color and to chalk- In my aforementioned applications, I have disclosed processes whereby both iron and sulphuric acid may be so completely eliminated from modified metatitanic acid that I obtain it of a uniform white color free from any gritty particles. The modified metatitanic acid so produced is superior to titanic oxide heretofore produced in both hiding and covering power. In its purest state, it contains 96.69% TiO and 4.31% H O,when dried at 100 6., corresponding to the formula 'H,Ti O It has a specific gravity of 3.20 to 3.30." It may contain more combined water owing to the presence of more highly hydrated oxides of titanium up to 10%., It is a fixed compound which-does not materially absorb water when exposed to damp atmosphere.

Calcined 'lliO obtainedby heating purified modified metatitanic acid as disclosed in my above mentioned applications ranges in specific gravity from 3.30 to 3.45, and purified modified metatitanic acid as disclosed in said applications ranges in specific gravity I from 3.20 to 3.30.

acid precipitated from hydrochloric acid soluti r ind containing a relatively small quantity of chlorine contained, air dried at 25 (1,7378% TiO, and 26.13% H O; dried at (3., 84.92 TiO and 15.08 H O; at 200 0., 9255 T10, and 7.45 E 0. The product dried at 200 (1, was not a fixed compound, in that it rapidly absorbed water from the air till it contained in excess of its contents dried at 100 C. The product dried at 100 C. was more nearly a fixed compound, but absorbed water till it con tained 17.90% H 0 and 82.10 'liO corresponding closely to the formula H 'li O or TiO(OH) I have found that when modified metatitanic acid is manufactured into paints Without admixture with other pigments, it produces a paint which has greater hiding power than have paintsmanufactured from any known pigments heretofore produced on a commercial scale. Also that the dried paint film is softer and more elas'ticthan are paint films from paints composed of white lead or zinc'oxide. Also that it dries slower than white lead or zinc oxide paints. In the .manufacture of my novel paint, I mix with my modified metatitanic acidsuch an amount of a pigment which dries to a hard surface as may be necessary to give my paint the characteristics required for the special use for which it is intended. I have found that there are many substances which will give the desired result. On account of their wide distribution and comparative cheapness, I prefer to use white lead or zinc oxide or a mixture of the two. l have used many proportions of these in paints ranging from one part zinc oxide to five parts modified metatitanic acid, to equal parts Zinc oxide and modified metatitanic acid and one part white lead to three parts modified metatitanic acid to three parts white lead to two parts modified metatitanic acid, and have obtained from them satisfactory results. I have found that the larger the proportion of zinc orv lead pigment used, the less covering and hiding power my paint will have. l have also found that, owing to the greater hiding power of my pigment, I may mix with my Further description, I believe, is uhnecessary to enable those skilled in the art to produce my said paints, since it follows that my modified metatitanic acid is mixed with the other constituents of the paint and mixed or ground with drying oil, such as linseed oil or other suitable vehicle, such as dissolved gum or othervarnish, in substantially the same manner as are white lead, zinc oxide or mixed paints, and is then ready for application in any suitable manner, to the surfaces to be covered, as by brushing on or otherwise, or the various ingredients of the paints may be ground separately with the vehicle and then brought together and mixed.

l have referred more especially to the use of my new pigment for the manufacture of white paint, but do not confine myself to such, for by substituting coloring matter for one or more of the white constituents, many tinted and colored paints may be produced, without departing from the spirit of my invention.

I claim:

- 1. A paint having as a pigment a white amorphous powder, consisting of a hydrated titanium oxide containing less than 10% of combined water, substantially as described.

'2. A paint having as a pigmenta hydrated titanium oxide containing less than 10% of combined water and substantially free from combined sulphuric acid, substantially as described.

3. A paint having as a pigment a hydrated titanium oxide containing less than 10% of combined water and substantially free. from iron and combined sulphuric acid, substantially as described.

1-. A paint'having as a pigment a titanium compound consisting essentially of five molecules of 'li0 combined with not more than three molecules of H 0, substantially as described.

5. A paint having as a pigment an amorphous powder consisting essentially of five molecules of 'lliO combined with not more than two molecules of H 0, substantially as described.

6. A paint having as a pigment a substance consisting essentially of a hydrated titanium oxide containing not more than 1.0% of water. in combination, substantially as described. p

smooth non-granular powder having a specific gravity not exceeding 3.45, substantially as described.

In testimony whereof I have hereunto set my hand.

FRANK E. BACHMAN. 

